Automated data storage libraries incorporate one or more robotics mechanisms for moving data cartridges around within the library. From time to time, these robotics mechanisms require maintenance actions. Maintenance is usually performed through a service door in the library's housing that allows personnel to access robotics mechanisms inside the library. All of the robotics mechanisms within the library are usually shut down any time the service door is open. This shut down is done for the safety of the personnel performing the maintenance on the robots.
The approach of shutting down the robotics mechanisms during maintenance is costly to the automated data storage library owner in terms of down time of the library and security for the data within. The library can perform no useful work while the service door is open and all of the robots are shut down. Even if maintenance is required on only one robotics mechanism, the other robots must be stopped in order to avoid possible collisions with the personnel. This means that no new data cartridges can be mounted into the read/write drives, and data cartridges currently in the read/write drives cannot be dismounted during maintenance operations.
The open service door also raises a question of security for the data cartridges within the library. Once personnel have access to the interior of the library, it is easy for them to add, remove, or rearrange the data cartridges resting in the library's storage cells. An audit of all data cartridges within the library is usually performed once the service door has been closed to verify that no manual manipulation of the data cartridges had taken place. For small libraries containing only a few data cartridges, an audit can be completed in several minutes. Very large data storage libraries containing thousands of data cartridges may require more than one hour to complete an audit. At a minimum, productive time of the library is lost during the audit. In a worse case scenario, data within the library has been either corrupted or lost.
What is desired is an approach that allows access to the robotics mechanisms from the exterior of the library while simultaneously blocking access to the data cartridges stored within. In large library systems containing multiple robots, it is desirable that the robots not being serviced are allowed to continue their normal operations. Preferably, the approach also blocks personnel access to these active robots while the one robot is being serviced.